蜘蛛酶对水奶牛产奶量、乳成分、体细胞数的影响

选取处于泌乳期中后期的水奶牛20头,按照胎次、泌乳天数与产奶量相近或相似的原则分为对照组和试验组,对照组奶牛饲喂基础日粮,试验组在基础日粮基础上每头水奶牛每日额外添加2g蜘蛛酶,研究其对水奶牛生产性能的影响。结果表明,整个试验期水奶牛产奶量都呈下降趋势,但是试验组降低幅度小于对照组;对照组体细胞数在试验结束时下降了25.90%,而试验组下降了47.53%,因此在牛乳体细胞数较低的水平下,在基础日粮中添加蜘蛛酶仍能起到比较明显的效果;另外,蜘蛛酶还可以提高乳蛋白和乳脂肪,并显著降低乳中活菌总数。     

哈密“密作”古枣园提质增效技术要点

正"密作"古枣是哈密区域独特的气候、地理条件下所形成的红枣优良品种,也是新疆独有的本地特色红枣公用区域品牌。我们总结了"密作"古枣园科学管理提质增效技术要点。1整形修剪简化树形,按枣树生长发育规律,一般利用短截、回缩、疏枝、拉枝、落头、抹芽、摘心等方法。丰产树形有多主枝疏层形、开心形。为解决     

Effects of Rice Variety and Growth Location in Cambodia on Grain Composition and Starch Structure简

The effects of variety and growth location on grain composition and starch structures were investigated using three rice (Oryza sativa L.) cultivars (Phka Romduol, Sen Pidao and IR66) with different amylose contents. All the three cultivars were planted in three different agro-climatic zones (Phnom Penh, Coastal and Plateau) of Cambodia. The protein content of polished grains increased when rice was planted at a location with higher average temperature, but their lipid content decreased. The amylose content and degree of branching were not greatly affected by the minor temperature differences among the growing locations. Starch fine structures characterized by the chain-length distribution were significantly different among the cultivars, but not significantly among different locations. The results suggested that protein and lipid biosyntheses were more sensitive to the environmental temperature than that of starch in rice grains.     

抗稻瘟病内生真菌DW22次级代谢产物醇提取方法的研究

从辽宁省西北地区根系土壤中分离得到DW22号内生真菌,液体培养后,分别用20%、40%、60%、80%、100%乙醇提取其次级代谢产物,依次编号为22-1、22-2、22-3、22-4、22-5。进行抗稻瘟病菌的抑制活性检测和方差及差异显著性分析。结果表明:20%乙醇提取DW22号内生真菌次级代谢产物对抑制稻瘟病菌有较好的效果。     

储粮生态系统的跨学科和多学科研究——加拿大曼尼托巴大学在粮食储藏研究上的最新进展

加拿大曼尼托巴大学的跨学科储粮研究团队对储粮生态系统的各个方面进行了系统的研究。该团队的最新研究活动包括:储粮生态系统建模,粮堆热点的发生和安全储存条件,粮堆气流流动,害虫在粮堆中的迁移、分布与对其取样、诱捕的关系,以及计算机图像处理技术。这些研究增进了我们对储粮生态系统的认识与理解,为粮食储运的安全性及高效率技术创新奠定了基础。     

Soil carbon characterization along the profile of two forest soils under Quercus pyrenaica

In light of concerns over climate change and increasing levels of CO2 in the atmosphere,it is of importance to investigate soil organic matter in Mediterranean forests at a profile scale.In-depth studies of the organic fraction are also of interest to improve understanding of carbon balance and to facilitate modelling of carbon fixation in forest soils.This research evaluates the relationships between diverse parameters such as colour,content,and form of soil organic matter(SOM).Two Quercus pyrenica ecosystems with soils classified as inceptisols with a xeric or dry moisture regime,and developed under a Mediterranean climate in Spain,were used to characterize SOM through the complete sequence of layers of the soil profile.The differentiating factor between the two ecosystems was slope gradient.Characterization was done using characteristics of humic substances(HS)as indicators of SOM turnover in inceptisols.Infrared analysis was used to further characterize the humic acids.As soil colour measurements are a tool for soil type classification and soil organic carbon prediction,the relation between HS colour measured by reflection and by transmission was determined in order to establish a relationship between measurement techniques.Infrared analysis and colour provided evidence of a different level of stabilization of HS from both soils,and between the different horizons.Oxidation of humic acids was found to be greater in deeper horizons than in the surface layers.An inverse relationship between HS colour measured by reflection and by transmission was revealed.Both soils showed a clear trend in which horizons presenting lower absorbance numbers showed higher figures of hue and value.A more marked accumulation of humified compounds was found in pedons,(the smallest unit or volume of soil that contains all the soil types),in the less steep slope.This might be explained in terms of the physiographic position affecting infiltration behavior and exposure to runoff.